She was married to United States Solicitor General Theodore Olson. In the mid 1990s, she was a chief investigator for the House Government Reform Committee. She was later a staff lawyer for Senate Minority Whip Don Nickles, before branching out on her own as a TV commentator and private lawyer. She was a frequent critic of the Clinton administration and wrote a book about First Lady Hillary Clinton, Hell to Pay: The Unfolding Story of Hillary Rodham Clinton. She was working on her second book, The Final Days: The Last, Desperate Abuses of Power by the Clinton White House (published December 2001) when she died. She had been a professional ballet dancer when younger, and had also been a prosecutor.
She was a passenger on board American Airlines Flight 77 when it was flown into the Pentagon in the September 11, 2001 Terrorist Attacks. She had reported the hijacking to her husband twice by phone about 20 minutes before the plane hit the Pentagon.
She was the subject of an eulogy by her husband at the Federalist Society on November 16, 2001. The occasion was the launching of the annual Barbara K. Olson Memorial Lectures. These lectures have a theme of "Limited Government and the Spirit of Freedom", to quote from the Society's website.